Aims. We present photoionization calculations for the spatially extended absorbers observed in front of the extended emission line spectrum of two high redshift radio-galaxies: 0943–242 (ze = 2.922) and 0200+015 (ze = 2.230), with the aim of reproducing the absorber column ratio, NCIV/NHI. Methods. We explore the effects of using different UV continua in the photoionization calculations. A comp...

We present spectroscopic observations of the damped Lyα absorber at redshift z = 1.9342 seen in the spectrum of the quasar Q0151+048A. The redshift of the absorber is greater than the redshift of the quasar, so the system resembles the zabs ≈ zem damped absorber at z = 2.81 towards the quasar PKS0528-250. We have previously reported the detection of Lyα emission from the latter absorber, one of...

We compare three different approaches to high-resolution contact lithography with special emphasis on contrast mechanisms for subwavelength structures. Masks with protruding metal absorbers, masks with absorbers embedded in the transparent background, and masks with air gaps and recessed absorbers are studied. Using the Green’s tensor technique we compute the light intensity distribution in the...

The propagation of ionizing radiation through model atmospheres of terrestrial-like exoplanets is studied for a large range of column densities and incident photon energies using a Monte Carlo code we have developed to treat Compton scattering and photoabsorption. Incident spectra from parent star flares, supernovae, and gamma-ray bursts are modeled and compared to energetic particles in import...

We describe recent discoveries of low column density (NHI ≤ 10 cm) H I Lyα absorbers made with the Hubble Space Telescope (HST) which have allowed us a first look at gas in local intergalactic space between us and the “Great Wall”. Despite the mere 2.4m aperture of HST, these new observations allow us to detect absorbers with column densities, NHI ≈ 10 12.5 cm, as low as those found using Keck/...

Fabrication of nano structured absorber is mandatory for reaping the enhanced thermal performance solar collectors. In this connection, carbon and aluminium composite was coated on substrate, which similar to hexagon shaped honey comb, developed. It characterized through X-ray Diffractometer (XRD), Fourier Transform Infrared (FTIR) spectrometer UV–Visible spectrophotometer (UV). also thermally ...

Plastic waste disposal is among the most challenging problems of current era. Therefore, new methods and applications for utilization plastics are increasingly needed. To find them, it essential to research develop material properties recycled plastics. The effect different ultraviolet light (UV) stabilizers on color stability, melt tensile mixed blends was studied in this paper. collected from...

Ultraviolet (UV) radiation-induced loss of dermal extracellular matrix is associated with skin photoaging. Recent studies demonstrated that keratinocyte-releasable stratifin (SFN) plays a critical role in skin collagen metabolism by inducing matrix metalloproteinase 1 (MMP1) expression in target fibroblasts. In the present study, we examined whether SFN released from UVB-irradiated epidermal ke...

Under UV-excitation, leaves emit red (RF) and far-red (FRF) fluorescence from chlorophyll and blue-green fluorescence (BGF) from hydroxycinnamic acids. In this study, the aim was to develop a fluorescence signature of wheat leaf ageing after the emergence of the lamina. FRF and BGF were examined in the first three leaves of 2-week-old wheat plants. It was investigated how FRF and BGF vary as le...